A typical computer system has several major components that include the processor, the memory controller hub, commonly known as the “Northbridge”, the I/O controller hub, commonly known as the “Southbridge”, memory modules, and a mass storage device.
The termination voltage reference of the interface between the Southbridge and the Northbridge is usually fixed. For example, when direct current (DC) coupling between a Southbridge and a Northbridge is to be used, a power supply terminated Southbridge can only connect to a power supply terminated Northbridge. The power supply terminated Southbridge cannot be connected to a ground voltage terminated Northbridge. As such, the fixed termination voltage reference of the Southbridge and Northbridge does not allow the interoperability of the Southbridge and Northbridge.